1. Field of Invention
In order to conserve energy, it is of utmost importance to insulate houses at windows and along outer walls. Cellular air bag insulators can be conveniently used in insulating walls and windows of houses and can be installed both on existing houses and on new houses under construction. A cellular air bag insulator is light weight and is compact in size when deflated. It can be installed on a window or along a wall without any construction modification and can be easily put up and taken down. Therefore, it is ideal for a non-permanent installation. A cellular air bag insulator made of a proper film material allows light to pass through, while imposing a high resistance to heat transfer. Therefore, it is an ideal insulator for a window area. Since a cellular air bag insulator can be put up along a wall and held in place easily and prevent air flow around it, it is an ideal insulator for a retrofit insulation of an existing wall. A cellular air bag insulator can also be used in insulating a process equipment such as a refrigerator, an evaporator, a distillation column and so on.
2. Brief Description of Prior Art
The most common method to reduce heat leakage through a house window is to use a double pane window. Because there is only one layer of confined space and it is not further compartmentized, convective heat transfer through it is still substantial. Furthermore, it is usually rather expensive to retrofit an existing window with a double pane unit. A common method to insulate a new wall is to put glass fiber insulation or rock wool insulation while it is under construction. It is difficult to retrofit existing walls by this method. One way to insulate an existing wall is to form a layer of foam plastic into the empty spaces within the wall. There have been some problems about release of toxic fume, formaldehyde, from such an installation and such a method is rather expensive.
A recent article in Popular Science Magazine, Jan. 1979, p. 76-79, describes a high "R" shade invented by Tom Hoper and manufactured by Insulating Shade Co. of Guilford, Connecticut. A high "R" shade has to be used in combination with a specially designed shade frame. A high "R" shade comprises five separate layers of aluminized mylar film and springy baffles running across the shade and is wound on an ordinary wooden roller. When the shade is pulled down, the baffles force the layer apart and expands the shade to a thickness of as much as 31/2 inches. The five layers thus create four air spaces within the shade, each of which is compartmentized by the baffles to reduce internal convection. It is these air spaces combined with the high reflection and low emission qualities of the aluminized Mylar that give the shade its resistance to heat flow. A special shade frame is used to prevent flow of air around the shade. A shade frame comprises extruded plastic shapes, flexible plastic side seals, flexible head seals and a weight added at the bottom. The flexible seals prevent air flow at the top and sides of the shade and the weight holds the bottom edge of the shade firmly against sill of the window to prevent air flow at the bottom.
It is noted that a cellular air bag insulator of the present invention does not require springy baffles and there is no need for a special frame to prevent air flow around it. Instead, because of the presence of an expandable honeycomb core in a cellular air bag insulator, a large number of air compartments in many layers are formed as the bag is inflated. Seals between the bag insulator and simple confining walls or the surface to be insulated are formed as the outer bag is inflated. The seals prevent air flow around the bag insulator.